Monday, June 15, 2015

Extinction Within Decades?

How the situation in the Arctic threatens most, if not all, life on Earth with extinction within decades.  

Vast amounts of methane

In the Arctic, vast amounts of carbon are stored in soils that are now still largely frozen. As temperatures continue to rise and soils thaw, much of this carbon will be converted by microbes into carbon dioxide or methane, adding further greenhouse gases to the atmosphere.

In addition, vast amounts of methane are stored in sediments under the Arctic Ocean seafloor, in the form of methane hydrates and free gas. As temperatures rise, these sediments can get destabilized, resulting in eruptions of huge amounts of methane from the seafloor. Due to the abrupt character of such releases and the fact that many seas in the Arctic Ocean are shallow, much of the methane will then enter the atmosphere without getting broken down in the water.

What makes the situation so dangerous is that huge eruptions from the seafloor of the Arctic Ocean can happen at any time. We can just count ourselves lucky that it hasn't happened as yet. As temperatures continue to rise, the risk that this will happen keeps growing.

What caused this dangerous situation?

This dangerous situation has developed because emissions by people have made the temperature of the water in the Arctic Ocean rise, and these waters keep warming much more rapidly than the rest of the world due to a number of feedbacks. One such feedback is the retreat of the sea ice, which in turn makes the Arctic Ocean heat up even more, as much sunlight that was previously reflected back into space by the sea ice, instead gets absorbed by the water when the sea ice is gone.

Without sea ice, storms can also develop more easily. Storms can mix warm surface waters all the way down to the bottom of shallow seas, reaching cracks in sediments filled with ice. This ice has until now acted as a glue, holding the sediment together. As the ice melts, sediments can become destabilized by even small differences in temperature and pressure that can be triggered by earthquakes, undersea landslides or changes in ocean currents.

As a result, huge amounts of methane can erupt from the seafloor of the Arctic Ocean and once this occurs, it will further raise temperatures, especially over the Arctic, thus acting as another self-reinforcing feedback loop that again makes the situation even worse in the Arctic, with higher temperatures causing even further methane releases, in a vicious cycle leading to runaway global warming.

Global impact

Such a temperature rise in the Arctic will not stay within the borders of the Arctic. It will trigger huge firestorms in forests and peatlands in North America and Russia, adding further emissions including soot that can settle on mountains, speeding up the melting of glaciers and threatening to stop the flow of rivers that people depend on for their livelihood.

These developments can take place at such a speed that adaptation will be futile. More extreme weather events can hit the same area with a succession of droughts, cold snaps, floods, heat waves and wildfires that follow each other up rapidly. Within decades, the combined impact of extreme weather, lower soil quality, crop failure and shortages of just about anything can threaten most, if not all life on Earth with extinction.

Food security

Will higher temperatures and carbon dioxide levels stimulate more plant growth? Will a warmer world allow more farming at higher latitudes? Firstly, the devastating impact of extreme weather events that come with a warming planet, will severely curb the prospects of farming anywhere. Successions of droughts, heat waves, wildfires, floods, storms and wild temperature swings could cause crop failure, while increased pests and diseases will have further debilitating impact.

Frost can ruin crops. Rice will only germinate at temperatures above 20°C (68°F). Cold snaps, hail storms and strong winds, can be expected to strike with increased intensity as the planet warms. More generally, a recent study finds that, while the global mean number of days above freezing will increase by up to 7% under a RCP 8.5 scenario (“business as usual” until 2100), the number of suitable growing days will decrease globally by up to 11% when temperature, water availability, and solar radiation are taken into consideration.

Indeed, each type of vegetation has its own optimal levels of water, sunlight, temperature and necessary nutrients in the soil. Changes in any of these levels could affect their growth negatively, with soil quality constituting an additional factor. Soil degradation can occur due to continued intensive single-crop farming or grazing. More extreme weather will make things worse, making it ever harder for farmers to continue to grow the crops they're used to.

This study finds that most temperate grasses and cereals, as well as many woody species, have temperature optima in the range from 15°C to 25°C (59°F to 77°F). Rice has a higher optimal temperature, but requires lots of water. Many legumes have a low net carbon dioxide uptake because of their high rate of pod and seed respiration. A rise in temperature will result in even greater respiratory losses from the pod and thus even less net carbon dioxide uptake. Legumes are important for their ability to fix nitrogen to the soil, an essential nutrient.

Recent research found that the situation is even worse than thought and that higher carbon dioxide levels will reduce the ability of plants to take up nitrogen. A recent study examined various types of ecosystems, including crops, grasslands and forests. "The nitrogen content in the crops is reduced in atmospheres with raised carbon dioxide levels in all three ecosystem types. Furthermore, we can see that this negative effect exists regardless of whether or not the plants' growth increases, and even if fertilizer is added," says co-author Johan Uddling, senior lecturer at the Department of Biological and Environmental Sciences at the University of Gothenburg.

What can be done?

What can be done to improve this situation? The Climate Plan advocates support for soil supplements containing biochar and olivine sand, to make it easier for soil to retain nutrients, moisture and microbes that benefit vegetation growth. The Climate Plan avocates that funding for such support be raised through fees on sales of livestock products and nitrogen fertilizers. This will reduce the use of fossil fuel-based fertilizers, while the pyrolysis to produce biochar can also produce hydrogen that can in turn be used to produce nitrogen fertilizers. Furthermore, moving away from farming livestock and associated single-crop farming will give more room for growing legumes alongside other crops. 

Two sets of feebates can work simultaneously and in parallel, i.e. separately, yet complementary, to facilitate the necessary shift to clean energy (yellow lines in top half of the image below) and to reduce levels of greenhouse gases in the atmosphere and ocean, while also increasing food security (yellow lines in bottom half of image below).

The situation is dire and calls for comprehensive and effective action as discussed in the Climate Plan


- Towards a Sustainable Economy

- Feebates

- Climate Plan

- Combining Policy and Technology

- The Mechanism leading to Collapse of Civilization and Runaway Global Warming

1 comment:

guyo smith said...

Not if any more Sam just when and the economic collapse train run parallel to the eco-crash train, it's a race do they cross tracks or maybe just go over the cliff together, big tectonic action or a disaster event would really speed things up,
what a lose, lose